Polymers containing aminoalkyl-phosphonates



United States Patent O US. Cl. 260--2.5 8 Claims ABSTRACT OF THEDISCLOSURE Selected phosphorus compounds, carbonyl compounds andalkanolamines are reacted to produce compounds of the formula:

wherein m and n are zero to two and m+n equals two; a is zero to one, bis one to two and a-l-b equals two; X is oxygen or sulfur; R R R and Rare organic radicals and R and R; can also be hydrogen, and R is analkyl group. Such compounds can be reacted with carboxylic compounds toproduce polyesters, or with epoxides to form polyethers. Such polyestersand polyethers, as well as the compounds themselves, can be reacted withisocyanates to produce polyurethane compositions. When the reaction iscarried out in the presence of a foaming agent, cellular products areproduced.

REFERENCE TO PRIOR APPLICATION This is a division of copendingapplication Ser. No. 158,877, filed Dec. 12, 1961, now U. S. Patent No.3,385,914.

This invention relates to novel phosphorus-containing monomers that arecapable of being polymerized to useful products. In other aspects, theinvention relates to novel phosphorus-containing polymers such aspolyesters and polyurethanes. In still further aspects, the inventionrelates to the production of useful polymer products such as foams,binders, castings, laminates and coating compositions.

It is known that polymers can be rendered fire-resistant byincorporating phosphorus therein. However, it is most desirable tochemically combine the phosphorus into the polymer toprevent the loss ofphosphorus by leaching or weathering of the polymer. In the past,phosphoruscontaining polymers have been prepared as esters of variousphosphorus acids wherein the phosphorus ester linkages formed theback-bone of the polymers. This approach has not been completelysuccessful because of the tendency of the phosphorus ester to hydrolizein the presence of water, which phenomenon results in the degradation ofthe polymer and the loss of its valuable physical properties. Hencethere is a need to overcome these difiiculties, and yet produce usefulpolymers with inexpensive materials.

Accordingly, it is an object of this invention to produce polymers thatare both fire-resistant and have good hydrolytic stability. It isanother object of the invention to produce novel monomers that arecapable of polymerizing to produce such polymers. It is a further objectto produce novel polyesters that contain phosphorus which are useful inthe preparation of castings, laminates, and reinforced plastic articles.It is still another object of the invention to produce novelpolyurethane compositions containing phosphorus that are useful in thepreparation of foams, adhesives, binders, laminates, coatings andpotting compounds. Still other objects and advantages of the presentinvention will be apparent to those skilled in the art uponconsideration of the following detailed description.

These and other objects are satisfied by providing novel compositonshaving the following chemical structure:

wherein m and n have a numerical value of zero through two, and m+nequals two; a has a value of zero or one, b has a value of one or two,and a-I-b equals two; X is oxygen or sulfur; R R R R are organicradicals selected from the group consisting of alkyl, cycloalkyl,alkenyl, aryl, alkylaryl, arylalkyl, and halo-substituted organicradicals of the foregoing group; and R can also be hydrogen, and R is analkyl group.

These hydroxyl-containing monomers can be reacted with carboxyliccompounds to produce polyesters, or with epoxides to form polyethers.When the polyesters are unsaturated they can be cross-linked to formthermosetting polymers by reaction with ethylenically unsaturatedmonomers and/or in the presence of free radical catalysts. Thepolyesters and the polyethers as well as the monomers themselves can bereacted with isocyanates to produce polyurethane compositions. When thereaction is carried out in the presence of a foaming agent, cellularproducts are produced.

The novel monomers of the invention are produced by reacting together anorganic compound, a carbonyl compound and a primary or secondary amine.The organic phosphites that can be used in the invention are thosehaving the chemical formula:

wherein m, n, R R and X are as defined hereinbefore. Among the preferredphosphorus compounds for use in practicing the invention are lower alkylphosphites such as dimethyl phosphite and lower alkenyl phosphites suchas diallyl phosphite. Other specific phosphites that can be used arethose wherein the radicals R and R are methyl, ethyl, isopropyl, butyl,hexyl, n-octyl, Z-ethylhexyl, decyl hexadecyl, phenyl, benzyl, tolyl,cyclohexyl, allyl, crotonyl, beta-chloroethyl, beta-bromoethyl,betamethoxyethyl, beta-ethoxyethyl, beta-butoxyethyl, betaphenoxyethyl,tetrahydrofurfuryl, tetra'hydropyranyl, and mixtures thereof.

In general, the length of the carbon chains or number of carbon atoms inthe aryl nuclei of the organic radicals of the phosphorus compounds isnot critical, and can vary over wide ranges. The lower limit is thelowest possible number of carbon atoms such as one carbon atom in thealkyl groups and six carbon atoms in the aryl groups, and the upperlimit is practical in nature. However, a higher percent by weight ofphosphorus may be incorporated in the polymer in instances where theorganic radicals attached to the phosphorus atoms are of minimum length,and thus the carbon atoms in the organic radicals R and R preferablyshould contain from one to about six to eight carbon atoms.

The carbonyl compounds are preferably aldehydes and ketones. Thepreferred aldehydes are those containing not more than eight carbonatoms. Suitable compounds of this class are formaldehyde, acetaldehyde,propionaldehyde,

butyraldehydes, benzaldehydes, furfural, 2-ethylhexanol,

3 :thylbutyraldehyde, heptaldehyde, glyoxal, pentaerythrose and thelike. The ketones that are useful in the invention lave the structuralformula:

R3-(|R4 lhe organic radicals R and R are groups such as methyl, :thyl,isopropyl, butyl, hexyl, n-octyl, 2-ethylhexyl, phenyl, Jenzyl, tolyl,cyclohexyl, allyl, and mixtures thereof. It s generally preferred thatthe number of carbon atoms in :ach organic radicals R and R do notexceed eight.

The preferred amines are those having the structural formula:

avherein a has a value of zero or one, b has a value of me or two, anda-f-b equals two, X is oxygen or sulfur and he organic radical R is analkyl group having not more vhan eight carbon atoms. Typical amines foruse in preaaring the compounds of the invention are ethanolamine,Z-aminopropanol, 3-aminopropanol, Z-aminobutanol, 3- iminobutanol,4-aminobutanol, di(2-propanol)amine, dif3-propanol)amine,di(2-butanol)amine, di(3-butanol) amine, di(4-butanol)amine, and thelike.

In the preparation of the polyfunctional monomers of his invention, itis preferred to maintain the reaction emperature at a low level in orderto inhibit the polymeri- :ation of the monomer products. Generally, itis preferred hat the reaction temperature be less than eighty degrees:entigrade, and preferably less than fifty degrees centigrade. Thereaction can be carried out in the presence of l solvent, if desired,the only requirement being that the :olvent is not reactive with respectto any of the reactants. luitable solvents are alcohols, such asmethanol, isoaropanol, butanol and the like; ethers such as diethylether, and dioxane, and hydrocarbons such as hexane, heptane, )ctane,benzene, and cyclohexane.

The following examples illustrate the preparation of the nonomers of theinvention.

' EXAMPLE 1 (a) Preparation of dimethyl-N-(2'-hydroxyethyl)-2-aminoisopropyl-2-phosphonate Twenty-two grams ofdimethylhydrogenphosphite, 12.2 grams of ethanolamine and two hundredmilliliters of methanol were mixed to yield a homogeneous solution.anhydrous sodium sulfate (50.0 grams), was added to the .olution. Asolution of 11.6 grams of acetone in fifty milliiters of absolutemethanol was added dropwise over a eriod of approximately ten minutes tokeep the temperaure of the reaction mixture under fifty degreescentigrade. Fhe hot mixture was stirred for about two hours at roomemperature until the temperature of the reaction was wenty-five degreescentigrade. The drying agent was filered off and the solvent wasevaporated.

The yield of crude material was eighty-nine to ninetyive percent. Theproduct was an almost odorless, coloress oil.

Analysis.Calcd. for C H NO P (percent): P, 14.66. ound (percent): P,15.0.

'b) Preparation and characterizations of the picrate ofdimethyl-N-(2-hydroxyethyl) 2 aminoisopropyl-Z- phosphonate ormula:

To a solution of 1.83 grams of dimethyl-N-(2-hydroxy-:thyl)-2-amino-isopropyl-2-phosphonate in two hundred milliliters ofanhydrous ether was added with stirring a solution of 3.07 grams ofpicric acid in four hundred milliliters of ether. A yellowishprecipitate formed.

The crude picrate is soluble in alcohols, slightly soluble in benzeneand hydrocarbons.

The crude picrate is recrystallized from hot chloroform by adding etherto the cloud point and cooling the solution to minus twenty degreescentigrade. It can also be recrystallized from ethylacetate ethermixtures. The purified salt, crystallizing as yellow needles, sinters atone hundred and twenty-seven degrees centigrade and melts at 128.5 toone hundred and twenty-nine degrees centigrade, (uncorrected) withdecomposition.

AnaIysis.C H N O P (percent): Calculated for C, 35.46; H, 4.80; N,12.72; P, 7.03. Found (percent): C, 35.47; H, 4.88; N, 12.73; P, 6.88,7.04 flame spectroscopy) EXAMPLE 2 (a) Preparation ofdimethyl-N-(2'-hydroxyethyl)- 2-aminoethyl-2-phosphonate Twenty-twograms of dimethylhydrogenphosphite, 12.2 grams of ethanolamine and threehundred milliliters of absolute methanol were mixed to yield ahomogeneous solution. Fifty grams anhydrous sodium sulfate were added tothe solution and a solution of 8.8 grams of acetaldehyde in fiftymilliliters of absolute methanol was then added dropwise with stirringover a period of approximately ten minutes, to keep the temperature ofthe reaction mixture under forty degrees centigrade. The hot mixture wasstirred for about two hours at room temperature. The drying agent wasfiltered olf and the solvent removed under vacuum.

The crude product obtained in a ninety percent yield was an almostcolorless, odorless oil. Phosphorus found, 15 .0 percent. (Calculatedfor C H O NP): 15.7 percent.

(b) Preparation and characterization of the picrate of dimethyl N(2-hydroxyethyl)-2-aminoethyl2-phosphonate One and two-tenths grams ofthe crude oily dimethyl- N-(2-hydroxyethyl)-2-aminoethyl 2 pho'sphonatewas completely dissolved in a mixture of fifty parts of ether andtwenty-five parts of methanol by volume. A solution of 3.5 grams ofpicric acid in a mixture of three hundred cc. of ether and twenty cc. ofmethanol was then added.

The turbid solution was filtered and the filtrate evaporated to drynessat twenty-five degrees centigrade under sixteen millimeters Hg. Thecrude picrate was recrystallized twice from hot ethyl-acetate by coolingat minus twenty degrees centigrade.

The yellow crystalline product sinters at one hundred and nine degreescentigrade, and melts at 111.5 to 112.5 degrees (uncorrected) withdecomposition.

Analysis.--Calculated for C H O N P (percent): C, 33.81; H, 4.49; N,13.14; P, 7.26. Found (percent): C, 33.80; H, 4.59; N, 13.17; P, 7.49,7.18 (flame spectros- EXAMPLE 3 Using the same general procedure as inthe foregoing examples, 15.6 grams of acetone was added portionwise withstirring into a solution of 22.0 grams of dimethyl hydrogen phosphiteand 21.02 grams diethanolamine dissolved in one hundred and fiftymilliliters of methanol and containing fifty grams of anhydrous sodiumsulfate. The temperature rose to thirty degrees centigrade during theaddition.

The reaction mixture was refluxed for five minutes and, after coolingand filtering off the drying agent, the solvent was removed as inExample 1.

The crude product is a very viscous, almost colorless liquid. Phosphorusfound: 12.9 percent (calculated for C H O NP 12.13 percent). Thecompound is named dimethyl N,N bis(Z-hydroxyethyl)-2-aminoisopropyl-2-phosphonate.

EXAMPLE 4 Twenty-two grams of dimethyl phosphite was dissolved in onehundred and fifty milliliters methanol. To the mixture was added fiftygrams anhydrous sodium sulfate and a solution of 11.6 grams of acetoneand twenty-five milliliters of methanol. Thereafter, 12.2 grams ofethanolamine dissolved in twenty milliliters methanol was added dropwiseover a period of four minutes, during which time the temperature rose toforty-one degrees centigrade. The reaction mixture was stirred forseveral hours and allowed to stand. The sodium sulfate was removed bysuction filtration and the solvent evaporated to provide a ninety-fivepercent yield of crude product.

EXAMPLE 5 To a mixture of 234.2 grams of diphenyl phosphite and onehundred milliliters methanol was added 61.1 grams of ethanolamine. Thetemperature rose to one hundred and twelve degrees centigrade, afterwhich an additional one hundred and fifty milliliters of methanol wereadded. The reaction mixture was agitated for nearly two hours. To amixture of two hundred and forty-seven grams of the resulting solutionand 31.5 grams of anhydrous sodium sulfate was added dropwise withagitation over a six minute period, a solution of 36.3 grams of acetoneand twenty-five milliliters of methanol. The reaction was allowed tostir for fifteen minutes.

EXAMPLE 6 To a mixture of 234.2 grams of diphenylphosphite and onehundred and fifty milliliters of methanol was added a solution of 72.6grams of acetone in fifty milliliters of methanol. An additional fiftymilliliters of methanol were added to the reaction mixture and after tenminutes, sixty-three grams anhydrous sodium sulfate was added.Thereafter 61.1 grams ethanolamine were added dropwise with agitationover a period of twelve minutes. After standing at room temperature fora period of time, the volatiles were evaporated and the crude productweighed three hundred and seventy-eight grams.

The polyfunctional monomers of this invention readily react withpolycarboxylic compounds to form polyesters. The preferred carboxyliccompounds are the carboxylic acids, acid halides and acid anhydrides,and mixtures thereof. The carboxylic compounds can be saturated orunsaturated or mixtures thereof depending upon the intended use for thepolyesters. Likewise the polycarboxylic compounds can be aliphatic,cycloaliphatic, aromatic or heterocyclic. Illustrative polycarboxyliccompounds include the following: phthalic acid, isophthalic acid,terephthalic acid; tetrachlorophthalic acid; maleic acid, dodecylmaleicacid; octadecenylmaleic acid; fumaric acid; aconitic acid; itaconicacid; trimellitic acid; tricarballylic acid; 3,3'-thiodipropionic acid;4,4-sulfonyldihexanoic acid; 3-octenedioic-L7-acid;3-methyl-3-decenedioic acid; succinic acid; adipic acid;1,4-cyclohexadiene- 1,2-dicarboxylic acid;3-methyl-3,S-cyclohexadiehe-1,2- dicarboxylic acid;3-chloro-3,5-cyclohexadiene-1,2-dicarboxylic acid; 8,12-eicosadienedioicacid; 8-vinyl-10-octadecenedioic acid; and the corresponding acidanhydrides, acid chlorides and acid esters, such as phthalic anhydride,phthaloyl chloride, and the dimethyl ester of phthalic acid. The resinscan be modified for special properties by using other selectedpolycarboxylic compounds. For example, 1,4,5,6,7,7 hexachlorobicyclo(2,2,1) 5 heptene- 2,3-dicarboxylic anhydride or acid andtetrachlorophthalic anhydride or acid can be used to impart additional 6flame resistance to the composition. The monomers of this invention canalso be reacted with monobasic acids, such as acetic acid, propionicacid, butyric acid and the like, to produce esters that are useful asplasticizers.

Highly useful polyethers are prepared by reacting the monomers of thisinvention with epoxides. Monomeric and polymeric epoxides can be used inthe practice of the invention. Examples of mono-epoxides that may beemployed in the practice of the invention are ethylene oxide, propyleneoxide, b-utylene oxide, isobutylene oxide, cyclohexane oxide,2,3-epoxyhexane, 3-ethyl-2,3-epoxyoctane, epichlorohydrin,epibromohydrin, styrene oxide, decylane oxide, triphenyl glycidylsilane, allyl glycidyl ether, methyl glycidyl ether, phenyl glycidylether, butyl glycidyl sulfide, glycidyl methyl sulfone, glycidylmethacrylate, glycidyl acrylate, glycidyl benzoate, glycidyl acetate,glycidyl octanoate, glycidyl sorbate, glycidyl allyl phthalate,phenyl-(p-octadecyloxybenzoyl)ethylene oxide,

and the like. The preferred monoepoxides are the monoepoxide substitutedhydrocarbons, the monoepoxy-substituted ethers, sulfides, sulfones andesters wherein the said compounds contain no more than eighteen carbonatoms. Typical diepoxides are: 3,4 epoxy-6-methylcyclohexylmethyl 3,4epoxy 6 methylcyclohexanecarboxylate, dicyclopentadiene dioxide,limonene dioxide, 4,4'-(diglycidy1)diphenylpropane, vinylcyclohexanedioxide. Examples of suitable polyepoxides are: epoxidized vegetableoils, and novolak polyglycidyl ethers.

The esterification or etherification of the phosphorus containingmonomers of this invention can be carried out at elevated temperatures,preferably not over one hundred and fifty degrees centigrade. Whenpolycarboxylic acids are used, the progress of the esterificationreaction can be monitored by measuring the quantity of water ofesterification that is produced. Small quantities of toluene or xylenecan be used as azeotroping agents to facilitate removal of the water.When acid halides are used, it is preferred to use solvents during thereaction. The acid halide can be dissolved in a suitable solvent such asbenzene and methylene dichloride and added to the hydroxyetherderivative also dissolved in the same or a similar solvent. The reactioncan be conducted at a temperature up to the boiling point of thesolvent. The solvent can be readily removed such as by stripping at thecompletion of the reaction. The progress of the reactions involving theacid halides can be monitored by measuring the quantity of hydrogenhalide evolved during the course of the esterification. Moreover, in thereactions involving this acid halides, it is often advantageous to use ahydrogen halide acceptor such as amines and strong bases. Preferredacceptors are tertiary amines such as pyridines, and triethylamine.

The unsaturated polyesters produced in accordance with this inventioncan be cured by cross-linking in the presence of a catalytic amount of aconventional polymerization catalyst for addition polymerization ofethylenically unsaturated materials, including free radical catalystssuch as benzoyl peroxide and other organic peroxides. The polymer canalso be cured by copolymerization with an ethylenically unsaturatedmonomeric material copolymerizable therewith, and preferably in thepresence of a catalytic amount of a polymerization catalyst such asmentioned above.

The ethylenically unsaturated monomers which can be used in curing orcross-linking the ethylenically unsat 'urated polymers of the presentinvention can be varied widely. While other materials can be used, it ispreferred that addition polymerization be practiced since no by-productammonia, water, etc., is formed and the problems resulting therefrom arenot experienced. The monomers useful in curing the thermoplasticunsaturated polymers include vinylidene compounds or mixtures thereofcapable of cross-linking ethylenically unsaturated polymer chains attheir points of unsaturation and usually they contain the reactive groupH C C-. Specific examples include styrene, chlorostyrenes, methylstyrenes such as alpha methyl styrene, p-methyl styrene, divinylbenzene, indene, unsaturated esters such as: methyl methacrylate, methylacrylate, allyl acetate, diallyl phthalate, diallyl succinate, diallyladipate, diallyl sebacate, diethylene glycol bis(allyl carbonate),triallyl phosphate and other allyl esters, and vinyl toluene, diallylchlorendate, diallyl tetrachlohophthalate, the lower aliphatic estersother than methyl of methacrylic and acrylic acids, the diacrylate,dimethacrylate, diethacrylate esters of ethylene glycol, etc. Themonomer can be admixed in the polymer in an amount sufficient to producea thermoset polymer and the admixture heated to an elevated temperaturein the presence of a suitable catalyst to cross-link or cure thepolymer. With proper catalyst systems such as cobalt naphthenate andmethylethyl ketone peroxide, room temperature cures are obtained.

In accordance with still other aspects of the invention, it is possibleto employ the improved polymers of the invention in the preparation ofplastic articles in general, reinforced plastic articles containing areinforcement such as cloth, glass fibers in the, form of roving,individual glass fibers, etc., and laminates or other filled resincompositions. Surprisingly, such prepared materials exhibit vastlyimproved physical properties such as discussed above for the polymers ofthe invention. Suitable reinforcements or laminations for preparing thereinforced articles and laminates include textile fibers or cloth, glassfibers or cloth, roving, etc. Castings may be prepared from the improvedpolymers of the present invention and such products likewise have beenfound to exhibit the improved properties of the polymers discussed aboveto a surprising degree. In general, well known processes of the priorart may be used for preparing the above-mentioned plastic articles,reinforced plastic articles, laminates or other filled resincompositions, and castings, with the exception of substituting theimproved polymer of the invention for that conventionally used. Usually,other changes in the process are not necessary. It is usually preferredthat a thermoset polymer be present in the finished article.

The following are examples of suitable reinforcing media that can beused with the polymers of the invention: glass fibers, glass mats, glasscloth, synthetic fibers such as Orlon, mineral fibers such as asbestos,natural fibers such as cotton, silk and wool, and metallic fibers suchas aluminum and steel.

Following are examples of fillers that can be used in the polymers ofthe invention: inorganic materials such as calcium carbonate, clay andpigments, and organic ma-' terials such as wood flour, cotton and rayonflock, sisal fibers and dyes.

Novel polyurethane compositions are prepared b reacting thephosphorus-containing monomers and the polyesters and polyethers of thisinvention with organic polyisocyanates. When polyurethane foams aredesired, the reaction with isocyanates is conducted in the presence of afoaming agent. In preparing these polyurethane compositions, the,components are preferably reacted in a ratio sufficient to provide abouteighty-five to one hundred and fifteen percent of isocyanate groups withrespect to the total of reactive groups such as amino, hydroxyl andcarboxyl present in the hydroxyl-containing material (and the foamingagent, if one is provided). The reaction temperature generally is abouttwenty to about one hundred and eighty degrees centigrade, althoughhigher and lower temperatures can be used.

It is also within the scope of the invention to blend thephosphorus-containing monomers and the polyesters and polyetherscontaining the phosphorus-containing compounds of this invention withother hydroxyl-containing materials, such as polyesters and polyethersprior to the reaction with an organic polyisocyanate. Such additionalpolyesters are the reaction products of polycarboxylic acids andpolyhydric alcohols, While the polyethers usually comprise the reactionproduct of a monoepoxide and a compound selected from the groupconsisting of a polyhydric alcohol, polyphenolic compound and apolycarboxylic acid. The polycarboxylic compounds and epoxides which canbe employed are any of the polycarboxylic compounds and monoepoxidesdisclosed hereinbefore. The preferred polycarboxylic compounds are thealiphatic and cycloaliphatic dicarboxylic acids containing no more thanfourteen carbon atoms, and the aromatic dicarboxylic acids containing nomore than fourteen carbon atoms. The preferred monoepoxides are themonoepoxide-substituted hydrocarbons the monoepoxy-substituted ethers,sulfides, sulfones and esters wherein said compounds contain no morethan fourteen carbon atoms. Polyphenolic compounds which can be employedare the reaction products of phenolic compounds with aldehydes, such asphenolformaldehyde resins. Illustrative polyhydric alcohols include thefollowing: glycerol; polyglycerol; pentaerythritol;'mannitol;trimethylol propane; sorbitol; trimethylolethane; butanediol;pentanediol; 1,2,6-hexanetriol; 2,2- bis(4-hydroxyphenyl)-propane, andthe like. Preferred polyols are the open-chain aliphatic polyhydricalcohols and polyalkylene ether polyols possessing from two to sixesterifiable'hydroxyl groups and containing no more than twenty carbonatoms.

A large number of various organic polyisocyanates can be used. Of thehydrocarbon polyisocyanates, the aryl and alkaryl polyisocyanates of thebenzene and naphalene series are more reactive and less toxic than thealiphatic members. Consequently, the aromatic compounds are preferred inthe present invention. The preferred compounds which are at present mostreadily available commercially are 2,4-tolylene diisocyanate,2,6-tolylene diisocyanate and mixtures thereof. However, others may beused, amongthem phenyl diisocyanate;

alpha-naphthyl diisocyanate; 4-tolylene diisocyanate;

n-hexyl diisocyanate; methylene-bis-(4-phenyl isocyanate);3,3'-bitolylene-4,4'-diisocyanate; 3,3-dimethoxy-4,4'-biphenylenediisocyanate; 1,5-naphthalene diisocyanate; 2,4-chlorophenyldiisocyanate; hexamethylenediisocyanate;

ethylene diisocyanate;

trimethylene diisocyanate; tetramethylene diisocyanate; pentamethylenediisocyanate; decamethylene diisocyanate; 1,3-cyclopentylenediisocyanate; 1,2-cyclohexylene diisocyanate; 1,4-cyclohexylenediisocyanate; cyclopentylidene diisocyanate; cyclohexylidenediisocyanate; p-phenylene diisocyanate; m-phenylene diisocyanate;4,4-diphenylpropane diisocyanate; 4,4'-diphenylamethane diisocyanate;1-methyl-2,4-phenylene diisocyanate; 4,4'-diphenylene diisocyanate;1,2-propylene diisocyanate; 1,2-butylene diisocyanate; 2,3-butylenediisocyanate; 1,3-butylene diisocyanate;

ethylidene diisocyanate;

propylidene diisocyanate;

butylidene diisocyanate; 1,3,5-benzene triisocyanate; 2,4,6-tolylenetriisocyanate; 2,4,6-monochlorobenzene triisocyanate;4,4-,4-"-triphenylmethane triisocyanate; polymethylenepolyphenylisocyanate and mixtures thereof. Higher isocyanates areprovided by the liquid reaction products of (1) diisocyanates and (2)polyols or polyamines; etc. In addition, isothiocyanates and mixtures ofisocyanates may be employed. Also contemplated are the many impure orcrude polyisocyanates that are commercially available.

Reaction. catalysts can be used in producing the polyurethanecompositions. The catalyst employed may be any of the known conventionalcatalysts for isocyanate reactions, such as tertiary amines, forexample, triethylamine, N- methyl morpholine, triethanolamine, etc., orantimony compounds such as antimony caprylate, antimony naphthenate, orantimonous chloride. In addition, tin compounds may be employed such asdibutyltin dilsurate,tri-n-octyltin oxide, hexabutylditin, tributyltinphosphate, or stannic chloride. Rigid or flexible polyurethane foams arethereby obtained. The rigid polyurethane foams utilize a highly branchedhydroxyl rich polyester or polyether having a hydroxyl number of betweenabout two hundred and nine hundred and fifty. The flexible polyurethanefoams utilize a linear relatively hydroxyl poor polyester or polyetherhaving a hydoxyl number of between about thirty and one hundred. If apolyester or polyether with a hydroxyl number between about one hundredand two hundred is employed, a semi-rigid polyurethane foam is usuallyobtained.

When the polyurethane compositions of the invention are foamed, anyfoaming agent commonly used in the art can be employed. Foaming agentsin this art are generally those materials that are capable of liberatinggaseous products when heated, or when reacted with an isocyanate.Preferably foaming is accomplished by introducing a low boiling liquidinto the catalyzed resin. The heat of reaction is then sufficient toexpand the mixture to a foam stable enough to retain its shape until theresin gels. Suitable liquids are the fiuorochlorocarbons boiling in therange of twenty to fifty degrees centigrade, and mixtures thereof, forexample, trichlorofiuoromethane, trichlorotrifluoroethane,dichloromonofiuoromethane, monochloroethane, monochloromonofluoroethane,difiuoromonochloroethane, and difluorodichloroethane.

Another foaming system that is suitable for carrying out the foamingreaction at an elevated temperature is found in U.S. Patent 2,865,869,which discloses and claims the use of tertiary alcohols in the presenceof strong, concentrated acid catalysts. Examples of tertiary alcoholsinclude: tertiary amyl alcohol; tertiary butyl alcohol;2-methyl-3-butyn-2-ol; l-methyl-l-phenylethanol; andl,1,2,2-tetraphenylethanol, etc. Examples of catalysts include: sulfuricacid; phosphoric acid; sulfonic acid; and and aluminum chloride; etc. Inaddition, various secondary alcohols and glycols may be used as:1-phenyl-1,2- ethanediol; 2-butanol; etc. Generally, secondary alcoholsshould be used with strong concentrated acid catalysts as above;however, certain secondary alcohols may be used without the acidcatalyst, e.g., acetaldol, chloral hydrate, etc. Other foaming agentsthat may be used include the following: polycarboxylic acids,polycanboxylic acid anhydrides, dimethylol ureas, polymethylol phenols,formic acid and tetrahydroxy methylphosphonium chloride. In addition,mixtures of the above foaming agents may be employed.

The following examples illustrate the preparation of novel polymericcompositions of the phosphorus-containing compounds of this invention.

EXAMPLE 7 An isocyanate prepolymer is prepared by adding 248.75 parts ofa commercial mixture of eighty percent of 2,4- tolylene diisocyanate andtwenty percent 2,6-tolylene diisocyanate to a reaction vessel andheating this material to ninety degrees centigrade. While vigorouslyagitating the isocyanate, 54.2 parts of dimethylN-(2'-hydroxymethyl)-2-aminoisopropyl-2-phosphonate is added dropwisewhile the temperature is maintained at or below one hundred and sevendegrees centigrade. Following completion of the addition, thehomogeneous reaction mixture is stirred at one hundred degreescentigrade for an additional thirty minutes and allowed to cool to roomtemperature under anhydrous conditions.

One hundred and twenty-five parts of the prepolymer is stirred withtwenty-eight parts of trichlorofluoromethane until the mixture ishomogeneous. To the mixture is added one hundred parts of a commercialpolyester, 0.25 parts of dibutyltin dilaurate, 0.25 parts ofN-methylmorpholine and 0.5 parts of silicone emulsifying agent, themixture is stirred vigorously for thirty seconds and the prefoam ispoured into a mold and permitted to stand at room temperature. The foamis cured for twenty minutes at eighty degrees centigrade. The foamproduct has a fine cell structure, a density of 2.5 pounds per cubicfoot, and is self-extinguishing when ignited.

EXAMPLE 8 The prepolymer described in Example 7 is blended in a mixingvessel with one hundred parts of a commercial polyester, 0.1 part ofN-methylmorpholine and 0.5 part of a silicone emulsifying agent, and themixture is stirred vigorously for one minute. The resulting polyurethanecomposition is applied to the surface of a sheet of steel and forms adurable coating that is highly flame-resistant and water-resistant.

EXAMPLE 9 A phosphorus-containing polyester was prepared as follows:

A polyester was prepared by reacting ten moles of trimethylolpropane andsix moles of adipic acid; the resulting hydroxyl number was five hundredand four. To five hundred grams of this polyester was mixed one hundredand twenty-five grams of dimethyl-N-(2-hydroxyethyl)- 2aminoisopropyl-Z-phosphonate. The mixture, which was non-homogeneous,was heated and stirred at one hundred and ten degrees centigrade for 4.5hours under vacuum. Methanol vapor was condensed and recovered from thereaction mixture. The resulting product was clear and had a phosphoruscontent of about 3.1 percent and a Gardner viscosity of two hundred andforty seconds at fifty degrees centigrade.

EXAMPLE 10 The polyester produced in accordance with Example 9 wasincorporated into a polyurethane composition as follows:

A polyurethane prepolymer was prepared by reacting eighty parts of acommercial mixture of tolylene diisocyanate isomers and twenty parts ofthe trimethylpropaneadipate prepared in Example 9. To one hundred andtwenty grams of the prepolymer was added one hundred grams of thephosphorus-containing polyester produced in Example 9, 0.5 gram siliconeoil, 0.5 gram tetramethylbutane diamine and thirty grams oftrichlorofluoromethane. The mixture was stirred for thirty seconds andpoured into a mold. The resulting foam had a phosphorus content of about1.3 percent, and was self-curing, selfextinguishing on ignition and hada low density.

In instances wherein the phosphorus-containing compounds of thisinvention are utilized with the hydroxylcontaining polymeric materialssuch as the polyesters and polyethers disclosed herein, it is preferredthat said hydroxyl-containing polymeric material have a hydroxyl numberbetween thirty and nine hundred and fifty.

As shown in the foregoing Example 9, the phosphoruscontaining compoundsof this invention can be reacted with polyesters, that are the reactionproducts of polycarboxylic compounds and polyhydric alcohols of the typedisclosed hereinbefore, to produce phosphorus-containing polyesters.Hence it is apparent that while this invention has been described withreference to certain specific embodiments, many variations will berecognized by those 1 1 skilled in the art that do not depart from thespirit and scope of the invention.

We claim: 1. An isocyanato-terminated polyurethane product of componentscomprising an organic polyisocyanate and a phosphorus compound of theformula:

wherein m and n are zero to two, and m+n equals two; X is oxygen orsulfur; R and R are alkyl, cycloalkyl, alkenyl, aryl, alkylaryl,arylalkyl or halogen-substituted organic radicals of the foregoinggroup; R and R are hydrogen, alkyl, cycloalkyl, alkenyl, aryl, alkylarylarylalkyl or halogen-substituted organic radicals of the foregoinggroup; and R is alkyl.

2. The polyurethane product of claim 1 wherein X is oxygen.

3. The polyurethane composition of claim 2 wherein X is oxygen.

4. A polyurethane composition having chemically combined therein aphosphorus compound of the formula:

wherein m and n are zero to two, and m-l-n equals two; X is oxygen orsulfur; R and R are alkyl, cycloalkyl, alkenyl, aryl, alkylaryl,arylalkyl or halogen-substituted organic radicals of the foregoinggroup; R and R are hydrogen, alkyl, cycloalkyl, alkenyl, aryl,alkylaryl, arylalkyl or halogen-substituted organic radicals of theforegoing group; and R is alkyl.

5. In a polyurethane composition comprising (I) a hydroxyl-containingpolymeric material having a hydroxyl number between 30 and 950 andselected from the group consisting of (a) a polyester comprising thereaction product of a polyhydric alcohol and a polycarboxylic compound,(h) a polyether comprising the reaction product of a monoepoxide and acompound selected from the group consisting of a polyhydric alcohol, apolyphenolic compound and a polycarboxylic acid, and (c) mixturesthereof; and (11) an organic polyisocyanate; a chemically combinedcomponent comprising the compound of the formula:

wherein R and R are alkyl, cycloalkyl, alkenyl, aryl, alkylaryl,arylalkyl or halogen-substituted organic radicals of the foregoinggroup; R and R are hydrogen, alkyl, cycloalkyl, alkenyl, aryl,alkylaryl, arylalkyl or halogensubstituted organic radicals of theforegoing group; and R is alkyl.

6. The polyurethane composition of claim 5 wherein thehydroxyl-containing polymeric material is a polyester, and thephosphorus compound of the formula is chemically combined in saidpolyester.

7. The polyurethane composition of claim 5 wherein the phosphoruscompound of the formula is chemically combined in the organicpolyisocyanate.

8. Foamed polyurethane compositions of claims 4, 5, 6, or 7.

References Cited UNITED STATES PATENTS 3,076,010 1/1963 Beck et al.260461 US. Cl. X.R.

qgggg UNITED sums PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,50l,h2l Dated March 17, 197

Invontor(o) Raymond R. Hindersinn and Miltiadis I. Iliopulos It iscertified that error appears in the above-identified patent and thatlaid Letters Patent are hereby corrected aa shown below:

r- Column 5, line 73, that portion of the compound reading "(2,2,l)should read ---(2.2.l)---. Column 7, line ll, the word"tetrachlohophthalate" should read ---tetrachlorophthalate---. Column 9,

line 15, the word "dilsurate" should read ---dilaurate---. Column ll,line 20, Claim 3, the claim reference numeral 2" should read ---h---.

SIGNED AND SEALED sen-m Anon:

Mnnm'h mm 1:. mm m. Melting Oifioor flomisaionor of Patents

